1. Field of the Invention
The present invention relates to a semiconductor device card receiving a circuit substrate which has electronic component parts assembled thereon.
2. Description of the Related Art
Conventionally, in such a semiconductor device card, as shown in FIG. 10, various kinds of electronic component parts are assembled on a circuit substrate 1. This circuit substrate 1 is received in a card case composed of a pair of upper and lower frame members to form the semiconductor device card. Each of the frame members comprises a sheet metal 5 for forming an upper or lower card surface and a resin-made frame 6 or 7 molded to peripheries of the sheet metal 5 for forming a card side frame, and the resin-made frames 6, 7 are connected to each other by means of an adhesive agent. These sheet metals serve to shield external radio wave noises and to prevent charging of static electricity. Therefore, as shown in FIG. 11, the upper and lower sheet metals 5, 5 are electrically connected to each other by a helical spring 4 inserted into portions of the resin-made frames 6, 7 in their physically connected conditions. A connector 3 is provided at a side opening composed by a pair of said frames members for use in external electrical connection.
In this semiconductor device card, strong connection between the upper and the lower frame members is required. Therefore, there has been proposed that the sheet metals is provided at their peripheral edges with bent portions and the circuit substrate is provided at its periphery with a resin-made frame portion so that the bent portions can be embedded in the resin-made frame portion in the Japanese Unexamined Patent Publication (Tokkaihei) No. 3-96396.
There are, however, several problems associated with the above-mentioned semiconductor device card. That is, since it is necessary to force the bent portions to be embedded into the heated resin-made frame portions or to embed the bent portions in the resin-made frame portions simultaneously with the molding of the later, the circuit substrate tends to be badly affected and the assembly working would become complicated. Accordingly, the connection between the bent portion and the frame portion can't help having recourse to the adhesive agent. But, the connecting strength tends to decrease as their sizes get smaller.
On the other hand, such a semiconductor device card is required to decrease the number of component parts and the number of assembling procedures to a minimum simultaneously with the downsizing. As a trial to decrease the number of component parts, portions of the opposed sheet metals are bent so as to be brought into contact with each other to eliminate the helical spring in the Japanese Unexamined Patent Publication No. 2-111595.